Some manufacturers of large and expensive components, such as those used in the aerospace or oil & gas sectors, have at one time or another had to slow down their internal turning processes in order to protect the parts that are being worked on. The reason is, of course, that a mistake can be extremely costly. However, one way of preventing errors while speeding up machining times would be to carry out regular checks on what is taking place within a closed machine tool. Knowing what is happening inside a component when carrying out internal turning can generate significant efficiencies and keep waste to a minimum, especially when machining slender components.

Working closely with customers across the globe, Sandvik Coromant has developed a connected solution that enables manufacturers to speed up the machining of high-value components, confident that anything untoward (that is, anything that moves beyond strictly set parameters) can be identified.

While Silent Tools technology from Sandvik Coromant is around 50 years old, the quantum leap comes from a new development that involves embedding sensors into the turning adaptors, making it much easier to fathom what is going on deep into a component being worked on behind a machine tool’s closed doors. This major advance in technology now makes it possible to extract accurate information from the machining process and – in real-time while cutting is taking place – share precisely what is happening with an operator via easily understandable and intuitive graphical displays.

Increased machining efficiency

The new development – Silent Tools Plus – features a damped adapter with embedded connectivity, delivering information such as vibration levels or the temperature in the damping system. By arming operators with this data, Silent Tools Plus offers a significant range of benefits to the manufacturer, most notably optimising process security and machining efficiency while avoiding damage to the machine tool and component, including surface damage.

In turn, this means less downtime through tool breakages and the ability to machine extremely costly materials and complex components at faster speeds, confident that the process is running satisfactorily.

Improved decision making

By displaying data such as vibration levels on an easy-to-understand dashboard, the system enables the operator to obtain an instant picture of what is happening and to get a tangible sense of the machining process as it is progressing. With the aim of improving decision making at the machine face, other data provided by Silent Tools Plus includes a history of what takes place during a cut, which is crucial when working on projects for manufacturers operating in such demanding industries as oil & gas or aerospace.

If there is any incident taking place outside set parameters – such as excess shaking or increased harmonics – the operator will be alerted to this instantly on the graphical display and will be able to take action accordingly to stop or adjust the machining process and avoid damage to the component.

Increased process security and better utilisation of equipment

The goal, then, is to make the machining process significantly more secure and to reduce the scrap rate to a bare minimum – or zero if possible. As mentioned, this aim is particularly important when the parts being worked on – such as aircraft landing gear or sub-sea components – can be extremely costly in terms of the materials alone. Being able to prevent such high-value components from being scrapped or reworked means that the investment in this type of technology has the capability of paying for itself over a very short timeframe.

Better utilisation of equipment can be achieved by reducing the amount of time that a machine is running without the tool in cut. Optimised machine utilisation is also available through the quick change interface between adapter and cutting head which makes for easy handling and accurate changing.

In addition, because the centre height setting functionality provided by Silent Tools Plus displays the level of the cutting edge, operators can quickly and easily set the height of the insert to the correct level before machining begins. The result of this is significantly better machining performance and longer insert tool life. Because data provided also covers such essential issues as surface finish quality, the operator is able to adjust the settings with the aim of optimising the process parameters.

Examples of indicators, then, that are included in the standard offering of Silent Tools Plus relate to vibration, surface roughness, in-cut, temperature and the centre height setting. The engineered solution that is also available offers additional features that cover load and deflection.

The standard offering from Sandvik Coromant is now suitable for adaptor diameters of 60mm, 80mm or 100mm with overhang up to 10 x diameter, while the engineered solution enables manufacturers to work up to almost 18 x diameter overhang and diameters above 100mm. Just three years ago, it was only possible to work on a maximum overhang of 14 x diameter but these limits have been extended through the acquisition of cutting tool knowledge over many decades, which has led to this latest development in boundary-breaking technology.


Essentially, this new functionality represents the eyes and ears within a component when internal turning is being carried out and the tool is simply not visible. Now that the operator is able to ascertain exactly what is going on in the cutting operation inside the component – in particular whether there are any disturbances in the process compared against agreed parameters – the key value that results from this is being able to make informed decisions based on actual and accurate data from the cutting process in order to increase machining security and productivity.

Being able to run operations faster while maintaining process security are major advantages for manufacturers who are looking to minimise waste for reasons of costs, delays and increased customer satisfaction.

In addition, with the move towards digital machining, Silent Tools Plus is one of several products that belong to the CoroPlus offer from Sandvik Coromant which contains connected solutions made ready for Industry 4.0. By delivering such powerful connectivity, the aim is to provide maximum support to manufacturers throughout their digital journey.